Field of the Invention
This invention relates to medical imaging systems. More particularly, this invention relates to operator interfaces in medical imaging systems.
Description of the Related Art
Cardiac arrhythmias, such as atrial fibrillation, occur when regions of cardiac tissue abnormally conduct electric signals to adjacent tissue, thereby disrupting the normal cardiac cycle and causing asynchronous rhythm.
Electrical activity in the heart is typically measured by advancing a multiple-electrode catheter to measure electrical activity at multiple points in the heart chamber simultaneously. A graphical user interface integrated with modern imaging systems for monitoring cardiac catheterization presents an abundance of dynamically changing information from the multiple electrodes to the operator, and facilitates efficient processing of the information by the operator.
Receiving atrial electrogram signals from intracardiac catheters is complicated by undesirable far field signal component mixed with near field electrical signals. In this environment near field signals indicate local activation, i.e., propagation of a signal through local regions being sensed by the electrodes. Detection of local activation is widely employed as an electrophysiological indicator of the local state of the heart. The far field electrical signals contain no useful information about local heart activation and only disturb the measurements.
Commonly assigned U.S. Patent Application Publication No. 2014/0005664 by Govari et al., which is herein incorporated by reference, discloses distinguishing a local component in an intracardiac electrode signal, due to the tissue with which the electrode is in contact from a remote-field contribution to the signal, and explains that a therapeutic procedure applied to the tissue can be controlled responsively to the distinguished local component.